1. Field of the Invention
The present invention relates to a control apparatus and a control method for controlling a forming apparatus which forms a surface having concavo-convex or three-dimensional object.
2. Description of the Related Art
Various methods are known as a method for forming desired concavo-convex structure and three-dimensional objects. For example, there are known a method in which a material is carved with a carving machine or the like and a method in which materials such as curable resin and gypsum are stacked. Meanwhile, a method in which an image is printed on a surface of a three-dimensional object is also known. For example, there are known a method in which an image is printed on a special sheet in advance by using a printing apparatus such as an offset printer and the sheet is pasted onto a target three-dimensional object and a method in which color materials are ejected directly onto a three-dimensional object by using an inkjet recording method. Surface characteristics such as sharpness and smoothness of the shapes of such concavo-convex and three-dimensional objects greatly affect the appearance and impression of the concavo-convex and three-dimensional objects.
Moreover, Japanese Patent Laid-Open No. 2004-299058 discloses a method of obtaining a hard copy in which three-dimensional appearance and texture is expressed by performing concavo-convex formation and image formation substantially at the same time by using an inkjet method. The following method is generally employed to express the concavo-convex in the aforementioned method. The concavo-convex is formed by dividing the concavo-convex into multiple layers and printing each of the layers over another layer.
As described above, the sharpness and smoothness of the formed concavo-convex greatly affects the appearance of the outputted object. However, the sharpness and smoothness cannot be appropriately reproduced by the processing of simply dividing the concavo-convex structure into multiple layers and printing each of the layers over another layer.
For example, in a case where the concavo-convex structure is formed by performing printing multiple times, steps are sometimes clearly visible in the concavo-convex layers due to reasons such as displacement between the layers, spreading of the ink, and contraction characteristic in curing. If such roughness is formed in a case where a smooth inclined surface is desired to be reproduced, smoothness of the inclined surface is lost and a desired texture cannot be obtained.
Meanwhile, reproduction of acute angles (for example, a cross-sectional shape like saw teeth) is sometimes difficult depending on the surface tension and spreading characteristics of a material used to form the concavo-convex structure. In this case, a sharp shadow formed by the concavo-convex of the surface is lost and a desired texture cannot be obtained.